X-ray diffraction for surfaces and buried interfaces

The application of X-rays to the structural characterization of surfaces an d interfaces, in situ and in UHV, is discussed on selected examples. Grazin g incidence X-ray diffraction is not only a very powerful technique for qua ntitatively investigating the atomic structure of surfaces and interfaces, but is also very useful for providing information on the interfacial regist ry for coherent interfaces or on the strain deformation, island and grain s izes for incoherent epilayers.